protocol race_ToDiffStates {
child:  M1();
parent: M2();

state S1:
    send M1 goto S2;
    recv M2 goto S3;

state S2:
    recv M2 goto S4;

state S3:
    send M1 goto S5;

state S4:
    send M1 goto S4;

state S5:
    recv M2 goto S5;
};
